Tension test device for human hair



Jam 311,, W5

J. E. HOPE TENSION TEST DEVICE FOR HUMAN HAIR Filed Dec. 23, 1946 Patented Jan. 31, 1950 STATES PATENT OFFICE 3 Claims.

This invention relates to a device for tensiontesting human hair for the purpose of securing data for later use in timing any one of a number of well-known hair-waving processes. It is well known in the art that the processing time for permanent waving hair varies considerably for each individual and even varies for the same person at different times of the year. Furthermore, it is known that the general physical condition of the person to whom the wave is being administered may materially affect the optimum processing time.

I have found that a reliable index for the proper time of processing resides in the relative tensile Another object is to provide an improved form of gripping device for holding opposed ends of a hair under tensile test, to avoid stress concentration near the grips.

A further object is to provide a device of this type having a pair of spaced terminals to which one or more hairs which have been removed from the head may be secured, one of the terminals being rotated under power and the other being pivotally mounted and adapted to operate a visual indicating device.

Another object is to provide a surface on the pivotally mounted terminal, which may act as a snubbing drum to avoid stress concentration at the point where the individual hair is attached to the terminal.

Other objects and advantages will appear hereinafter.

In the drawings:

Figure 1 is a front elevation of a testing device embodying my invention;

Figure 2 is a side elevation thereof Figure 3 is a rear elevation, showing internal workings of the device;

Figure 4 is a sectional detail, taken substantially on the lines 3-4, as shown in Figure 3; and

Figure 5 is a fragmentary plan view, showing details of the hair-testin terminals illustrated on an enlarged scale.

Referring to the drawings, a housing or case Ill, provided with a slanting panel I I and a shelf I2, may be provided with feet I3 for resting on any convenient support, not shown. A primary terminal I 4, extending upwardly from the shelf I2 and rotatable about a vertical axis, is provided radial slot I6, extending axially from the outer end of the terminal. The primary terminal I4 is provided with a drive shaft I'I, driven from an electric motor I8 by means of gearing I9.

A secondary terminal 20 extends upwardly through a slot 2I in the shelf I2 and has its lower end secured in a pivot shaft 22, pivotally supported in a bearing 23. An arm 24, secured to the pivot shaft 22, is connected at one end to a tension spring 25 and at the other end to a flexible line 26. The spring 25 is attached to the case I0 at 21. The flexible line 26 is wound around a spool i'ng surface 28, provided on the back side of the indicator dial 29. An opening 30, in the case I0, exposes indicia 3I on the indicator dial 29 for visual inspection. The dial 29 is rotatably supported relative to the case ID by bearing means, not shown.

The outer end of the pivotally mounted secondary terminal 20 is provided with a cylindrical Eur-- face 32 and a radial slot 33 interrupting the surface and extending inwardly from the outer end of the terminal 20. The slot 33 is positioned parallel to the axis of the pivot shaft 22.

In operation, a single hair, which has been removed from the head of a person whose hair is to be waved, is inserted into the slot 33 and wrapped one or more times around the cylindrical surface 32. The hair, which may be designated 34, is then passed through the slot I6 in the upper end of the primary terminal I l. The motor drive switch 35 on the shelf I2 is then actuated for energizing the motor I8 and causing the terminal M to rotate slowly. The hair 34 is preferably wrapped one or more times around the cylindrical surface I5 in the direction of its rotation before passing through the slot is so that a snubbing effect on the cylindrical surface I5 is obtained, and stress concentrations thereby avoided, which might cause premature failure of the hair at the point where it enters the slot I6. The hair is wrapped around the cylindrical surface 32 for the same reason, so that breakage will not occur at a point adjacent the slot 33.

As the primary terminal I4 slowly revolves, the secondary terminal 29 is caused to pivot in a clockwise direction, as viewed in Figure l, and thereby rotate the pivot shaft 22. Turning movement of the pivot shaft causes the flexible line 26 to rotate the indicator dial 29 and thereby cause indicia 3! on the dial 29 to pass under the index 36, extending across the opening 36. The operator watches the dial 29 and notes the relative position of the indicator 35 and indieia SI at the inwith a cylindrical surface I5 interrupted by a stant that the hair 34 fails in tension. The spring 25 is selected so that failure will occur before the terminal 20 reaches the extreme end of its travel in the direction toward the primary terminal l4. Upon failure of the hair 34, the spring as returns the arm 24 and terminal 20 to their initial position. The test may be repeated with three or four additional hair samples, in order to secure a number of readings of the dial 223 which may be averaged. From this information, the operator determines the time which should be used in the hair waving process. A clock timer 35 is mounted within the case and is provided with an adjustable knob 31. The clock timer 36 and the drive motor it are connected to the power supply 38. An outlet plug 39 is provided on the side of the case for connection to an electric hair waving machine, not shown, and the clock timer 36 is adapted to maintain a supply of electrical ener y at the plug 39 for the time period selected by the knob 31 and dial 40 connected to the clock timer 36 An indicator lamp 4| is energized whenever the clock timer 26 is in operation. A switch 42 is provided on the shelf !2 for initiating action of the time clock 36 The knob 43 is connected to the indicator dial 29 in order that the dial 29 may be returned to its initial position at the start of a new test.

Having fully described my invention, it is to be understood that I do not wish to be limited to the details herein set forth, but my invention is of the full scope of the appended claims.

I claim:

1. A tension testing device for a human hair or the like, comprising the combination of walls forming a housing, one of the walls having an opening and a slot therein, a primary terminal projecting through the opening and having a cylindrical surface, means supporting said primary terminal on the housing for rotation about the axis of said cylindricalsurface, selectively operable power means within the housing for rotating the primary terminal, a secondary terminal pivotally mounted for angular movement toward and away from the primary terminal and projecting through said slot, resilient means Within the housing opposing pivotal movement of the secondary terminal toward the primary terminal, means operably connected to the secondary terminal adapted to provide a visual indication of the angular move ment thereof, and means near the exposed end of each terminal for securing a hair thereto.

2. In a device for tension testing a human hair or the like, the combination of walls forming a housing, one of the walls having an opening and a slot therein, primary and secondary terminals extending through the opening and slot respectively and each having a cylindrical surface near a projecting end thereof, means in the housing supporting said primary terminal. for rotation about the axis of its cylindrical surface, selectively operable power means in the housing for rotating the primary terminal, the secondary terminal being pivotally mounted for angular movement in the slot toward and away from the primary terminal, resilient means opposing pivotal movement of the secondary terminal toward the primary terminal, and dial means on the housing operably connected to the secondary terminal adapted to provide a visual indication of the angular movement thereof.

3. In a device for tension testing a human hair, or the like, the combination of a housing having a front panel and a horizontal shelf, the shelf having an opening and a slot extending therethrough, an upwardly extending primary terminal extending through the opening and mounted for rotation about a vertical axis and provided with a coaxial cylindrical surface, selectively operable means within the housing for rotating the primary terminal, an upwardly extending secondary terminal pivotally mounted about a horizontal axis for angular swinging movement within said slot toward and away from the primary terminal, resilient means within the housing opposing pivotal movement of the secondary terminal toward the primary terminal, dial means on the front panel operably ccnnected to the secondary terminal and adapted to provide a visual indication of the pivotal movement thereof, and means near the upper exposed end of each terminal for securing a hair thereto.

JOHN E. HOPE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,456,596 Hugentobler May 29, 1923 1,708,359 Coune Apr. 9, 1929 1,837,577 Nessler Dec. 22, 1931 2,217,080 Ruch Oct. 8, 1940 

